Dust catcher



Nov. 28, 1933. E, PRA-r 1,937,095

DUST CATCHER Filed March 28, 1928 Patented Nov. 28,u 1933 UNITED STATES;

DUST CATGHEB Emile Prat, Paris, France Application March 28, 1928, Serial No. 285,288, and in France April l, 19t? z claims. (cl. isa-se).

The invention relates to mechanism for removing dust contained in gases and more particularly dust carried along in the smoke from a furnace.

Various schemes have been resorted to for the elimination of such dust by catch-pockets and by familiar dust eliminating apparatus.

My invention consists of a combination of instrumentalities, which 'in practice have been found to be highly successful.

The accompanying drawing shows an embodiment thereof.

Figs. 1 and 2 are vertical sections on planes at right angles to each other;

Fig. 3 is a plan view in section along line 3-3 of Fig. l.

A centrifugal blower a has inlets ai, a1 at its two ends for the gas coming through the foot b1, of a stack, the upper part of which is shown at b.

I'he casing c of the blower is of the usual snail type and is placed within the wall of the stack b b1. Ordinarily the casings of such blowers extend about one revolution of a spiral, to about the point d.

u In the present case, the casing proper of the blower is extended by extension e which conducts the gas around the casing c and up through a pipe f to the upper part b of the stack. The dust in the gas, by reason of the centrifugai movement induced by the blower a, is pro- :lected to the periphery of the casing and is carried beyond the point d and down into the extension e. In some installations, such an extension of thecasinghasbeenshapedandused asacatch box for the dust (from which it is removed at intervals).

I have found in practice that thorough precipitation of dust doesr not take place in such a pocket or catch-box. But by providing a current Aoofthegastopositivelytakethedustoutofthe blower casing, the separation effected by such a blower and casing is greatly improved. For this purpose. I provide a pipe a' communicating with the extension e and leading into a centrifugal separator or so-called cyclone k of any usual or suitable design, having a vertical axis. A certain quantity of gas is carried with the dust accumulated in the extension e and is blown into the cyclone k in a descending spiral. The gyratory motion is obtained by `directing the pipe i tan'- -gentially to the periphery of the cyclone k. the opening of said pipe into the latter being shown at a behind the plane of Figure 1 .l .The top of the cyclone k opens at h into the f oot ln of the open into said foot b1, the-blower withdraws the gas from the cyclone k through h, in and o1, and

stack so that, as the inlets ai of rthe blower a also the opening i, and the cleaned gas passes through h back to the blower a.

I am aware that a cyclone or gyration chamber has already been employed i'orseparating dust but not in combination with a centrifugal blower having an outlet directed to a cyclone adapted to cause gyration about a vertical axis. It is also known to allow dust to pass from the periphery of a centrifugal blower into a settling chamber, but the latter has not been formed as a cyclone or vertical gyration chamber, the extension not having been led tangentially to the periphery of such a settling chamber.

A better separation of dust can, however, be obtained by the combined action: ilrstvof the vertical cyclone k adapted to cause gyratory movement of the gas containing dust branched of! from the outlet casing of a centrifugal blower,

second of the suction from said chamber through the outlet h back to the blower, which forces the dust from the extension e into the cyclone k.

Various modifications of the embodiment illustrated can be made byy those skilled in the art without departing from the invention defined in the following claims.

What I claim isz- 1. The combination with a smoke stack of a centrifugal blower enclosed in a casing within the stack with inlets communicating with the lower portion of the stack and with a main outlet leading to the upper part of the stack, of a centrifugal dust separator having a tangential inlet in communication with a small outlet through the casing of the blower and having its gas outlet communicating with the inlet of the blower so that the blower exerts a suction and causes the dust-laden gas to ilow through the separator with sufiicient velocity and centrifugal eect to separate the dust.

2. The combination with a smoke centrifugal blower enclosed in a easing within the stack with inlets communicating with the lower portion of the stack and with a main outlet leading to the upper part of the stack, of a centrifugal dust separator located in the lower part of l the stack having a tangential admission conduit communicating with a smaller outlet from the lower part of the blowerfcasing and having its outlet into the lower part of the stack so that the blower causes a suction which draws the dustn. laden air through the separator with sufficient velocity and centrifugal force to eil'ect a separation of the d ust therein.

.. EMILE PRAT.

therebycompelsthegascontainingdusttopassfromtheextensioneandpipeiintothecyclone w 7c. 'Ihedustfsilstothebottomofkoutthrough mok-or s m 

